Objective To observe the characteristics of spectraldomain optical coherence tomography (SD-OCT) and fundus autofluorescence (FAF) in acute and chronic central serous chorioretinopathy (CSC).Methods Seven-three eyes of 67 patients with CSC diagnosed by slit-lamp microscopy, fundus photochromy, fundus fluorescein angiography (FFA) and indocyanine green angiography were enrolled in this study. All the patients were examined for FAF and SD-OCT. The patients were divided into acute CSC group (37 patients, 37 eyes) and chronic CSC group (30 patients,36 eyes) according to the clinical features and FFA images. According to the OCT feature in retinal detachment area, they were divided into three categories, which including intact, non-intact and atrophy outer segment, respectively. According to the FAF characteristics, they were divided into hyper-FAF, hypo-FAF and mixed type, respectively. The characteristics of SD-OCT and FAF of both acute and chronic CSC patients were evaluated and analyzed. Results In acute CSC group, 19 eyes (51.35%) were hypo-FAF, 18 eyes (48.65%) were hyper-FAF. In chronic CSC group, two eyes (5.56%) were hypo-FAF, 16 eyes (44.44%) were hyper-FAF, and 18 eyes (50.00%) were mixed type. There was significant difference between both groups (chi;2=31.872,P=0.000). The SD-OCT results showed that in acute group, 15 eyes (40.54%) were intact outer segment, 18 eyes (48.65%) were non-intact outer segment, and four eyes (10.81%) were atrophy outer segment. In chronic group, five eyes (13.89%) were intact outer segment, 17 eyes (47.22%) were non-intact outer segment, and 14 eyes (38.89%) were atrophy outer segment. There was significant difference between both groups (chi;2=10.572,P=0.005). Conclusions The FAF characteristics of acute and chronic CSC mainly manifests hypo-FAF and mixed type, respectively. The OCT characteristics of acute CSC mainly manifests intact outer segment and non-intact outer segment, but non-intact outer segment and atrophy outer segment in chronic CSC.
Objective To observe the characteristics of fundus autofluorescence （AF） distribution at the posterior pole in normal subjects. Methods Seventy-nine normal subjects （156 eyes）were studied. Confocal scanning laser ophthalmoscope (cSLO) HRA2 was used to obtain the AF average image at the posterior pole. The distance was calibrated by Digimizer image analysis system. With umbo as the center, the macula was divided into foveola, fovea, parafovea and perifovea areas which with the radius 175, 750, 1250 and 2750 mu;m respectively. Each area was further divided into inferior, superior, temporal and nasal quadrants by two radial lines angle of 90deg;, except for foveola. The AF intensity in four quadrants of different macular regions and optic disc were measured. The AF intensity in vertical and horizontal direction of umbo was also measured. Then the effects of age, eyes, and gender on AF intensity in four quadrants of different macular regions were analyzed. Results There were statistically significant differences in AF intensity among optic disc and four quadrants of macular regions （F=528.648, P＜0.05）. AF distribution was V-type in vertical direction and M-type in horizontal direction. There were statistically significant differences between age groups in foveola, inferior parafovea, temporal parafovea, inferior perifovea, superior perifovea and temporal perifovea （P＜0.01）. There were no statistically significant differences between the two eyes （P＞0.05）. Between genders group, there were statistically significant differences in foveola, superior fovea, inferior fovea, nasal fovea and temporal perifovea （P＜0.05）; no statistically significant differences in the other quadrants （P＞0.05）. Conclusions The distribution of AF intensity is inhomogeneous in macular regions and four quadrants of each region in normal subjects. AF intensity increases with aging. AF distribution is symmetrical in both eyes. There is probably no correlation between gender and AF intensity distribution.
Objective To observe the autofluorescence （AF） manifestation in related lesions of periphery retinopathy.Methods Sixty eyes of 42 patients with periphery retinopathy underwent the examination of Optomap fundus photograph (200deg;) and fundus fluorescein angiography (FFA). The HRAⅡ melaninrelated nearinfrared fundus autofluorescence (NIA, excitation 795 nm) and lipofuscinrelated fundus autofluorescence (FAF, excitation 488 nm) were measured for all the patients. The AF was recorded with nine images per second, and then a final AF image with 55deg; view and 822times;768 pixel was generated by the HRA. AF images can be valuable or valueless if there was or was not visible blood vessels and related retinal tissues on the image. AF from lesion regions can be normal or abnormal fluorescence comparing to the normal vascular and retinal tissue AF. The abnormal fluorescence was divided into no AF, weak AF and b AF relative to the background grayscale. The grading consistency of abnormal fluorescence based on FAF and NIA examination was comparatively analyzed. Results Valuable AF images were captured in 53/60 eyes （88.33%）and valueless AF images were captured in 7/60 eyes （11.67%）. Among 53 eyes with valuable AF image, NIA showed normal fluorescence in 28 eyes （52.83%），abnormal fluorescence with sheetlike, dotshaped or stripped in 25 eyes （47.17%）; FAF showed normal fluorescence in two eyes （3.77%）, abnormal fluorescence with sheetlike, scattered along vessels or pigments in 51 eyes （96.23%）. Twentyfive eyes with abnormal fluorescence were observed both in two examinations, including same grades in 18 eye （72.00%） and different grades in seven eyes （28.00%）. Conclusion The AF manifestation with different levels exists in related lesions of periphery retinopathy.
To investigate the characteristics of fundus autofluorescence (AF) in the leakage site of central serous chorioretinopathy (CSC). Methods Sixty-seven CSC patients (67 eyes) underwent fundus fluorescein angiography (FFA) examination with a confocal scanning angiography (HRA2). Autofluorescence was elicited by the wavelength of 488 nm. The patterns of autofluorescence corresponding to the leakage site on FFA were observed. All the enrolled patients were grouped by age (agele;45 in 47 eyes and age ＞45 in 20 eyes) and courses (acute CSC in 25 eyes and chronic or recurrent CSC in 42 eyes), the patterns of autofluorescence were analyzed respectively. Results There are 4 patterns of AF in the leakage site on FFA of CSC patients: no AF changes, punctuate hypo-AF, expanded hypo-AF or speckled AF, hyper-AF. The percentages of those patterns in all 67 eyes are 52.2%, 23.9%, 14.9% and 9.0% respectively. The percentages of those patterns in the group of age le;45 (n=47) are 55.3%, 23.4%, 14.9% and 6.3% respectively. The percentages of those patterns in the group of age ＞45 (n=20) are 45.0%, 25.0%, 15.0% and 15.0% respectively. The percentages of those patterns in acute CSC (n=20) are 80.0%, 16.0%, 4.0% and 0% respectively. The percentages of those patterns in chronic or recurrent CSC (n=42) are 35.7%, 28.6%, 21.4% and 14.3% respectively. Conclusion There are different patterns of fundus autofluorescence in different age and courses of CSC patients.
Objective To observe the effect of epidermal growth factor (EGF) on integrin alpha;5 expression and its influence on human retinal pigment epithelium (RPE) cells.Methods Human RPE cells were treated in vitro with 0.1,1.0,10.0,20.0 and 100.0 ng/ml of EGF, the mRNA and protein of integrin alpha;5 was measured by reverse transcription polymerase chain reaction（RT-PCR）and flow cytometry. Human RPE cells were cultured under 4 conditions including DMEM/F12,DMEM/F12+10 ng/ml EGF, DMEM/F12+10 ng/ml EGF+rabbit antihuman integrin alpha;5 antibody (1∶100)，DMEM/F12+10 ng/ml EGF+rabbit antihuman vimentin antibody (1∶100), and their proliferation and migration were measured by methylthiazole tetrazolium（MTT）and Boyden chamber.Results The integrin alpha;5 mRNA level of human RPE cells was not changed after 12 hours of EGF stimulation (F=0.618, P=0.687), however it was induced in a dosedependent manner after 24 and 48 hours of EGF stimulation (F=465.303, 212.340; P=0.000,0.000).The protein level of integrinalpha;5 was higher in 10 ng/ml EGF stimulation compared with the control group and 0.1 ng/ml group（P＜0.01）.MTT and Boyden chamber showed that the integrin alpha;5 expression increased the proliferation and migration of human RPE cells. Conclusion EGF can induce integrin alpha;5 expression,thus increase the proliferation and migration of human RPE cells.
Objective To investigate the possible effects of phosphorylated signal transduction and activator of transcription3 (STAT3) in the formation of choroidal neovascuarization (CNV) induced by photocoagulation in rats. Methods The CNV model in rats induced by photocoagulation was established, and the expression of phosphorylated STAT3 at the early stage in CNV were observed by immunofluorescence. To set up the hypoxia model, the specific inhibitor of Janus kinase 2 (JAK2), AG490 was mixed into cell culture fluid and then cultured for 0,1 hour,3,6,12,and 24 hours.Retinal pigment epithelial (RPE) cells proliferation activity were detected by flow cytometry (FCM).the expression of hypoxiainducible factor (HIF)1α and vascular endothelial grow factor (VEGF) mRNA were detected by reverse transcriptase polymerase chain reaction (RT-PCR); the expression of HIF1α protein was detected by Western blot; the content of VEGF in the supernatant of cell culture fluid was measured by enzyme linked immunosorbent assay (ELISA). Results Phosphorylated STAT3 highly expressed in CNV areas in rats 3 days after the photocoagulation. The proliferation activity of human RPE cells under hypoxia condition significantly decreased after inhibition of JAK2/STAT3 signal transduction pathway (t=1.472, 3.566,2.391,6.420; P=0.054,0.038,0.042,0.016). The expression of HIF-1α and VEGF mRNA increased gradually with increasing time of hypoxia;while the expression of HIF1α and VEGF mRNA and the activation of HIF1α protein in cultured human RPE cells with the JAK/STAT3 signal transduction pathway blocked by AG490 were suppressed obviously under hypoxia condition (t=0.07,0.02,0.01, P<0.05); the content of VEGF in RPE cells supernatant decreased significantly (t=1.330,1.106,2.828,7.742,5.610,6.894; P=0.082,0.063,0.014,0.002,0.016,0.011). Conclusion STAT3 may be involved in CNV formation, which may partly dependent on JAK2/STAT3 signal transduction pathway regulating the expression of HIF-1α and VEGF in RPE cells.
Objective To investigate the feasibility of gene transfection into retinal pigment epithelial (RPE) cells and photoreceptors (PRs) in vivo electroporation. Methods A total of 147 Sprague-Dawley (SD) rats were divided into 5, 10, 15, 20, 25, 30 and 35 V group according to different voltage. The right eyes of rats underwent the injection of eukaryotic expressive plasmid of enhanced green fluorescent protein (EGFP) pEGFP-N1 into subretinal space as experimental eyes; the left eyes were injected with TE buffer as control eyes. Each group was divided into RPE and RP subgroups according to different transfection direction. There were same parameters of 99 ms pulse width, 0.5 s pulse interval and 5 consecutive pulses except different voltage in groups. With a negative charge in the electric field was transfected into RPE cell layer, reverse electrode set to be transfected into PR cell layer. Retina mounts were made on seven days after transfection and the fluorescence of EGFP was photographed by fluorescent microscope. The expression of EGFP mRNA and protein were detected by reverse transcription polymerase chain reaction technique (RT-PCR) and Western blot.Results On seven days after transfection, in RPE subgroups, there were no specific fluorescence expressions in RPE cell layer and retina mounts of control eyes, while there were fluorescence expressions in experimental eyes. Western blot showed that the grayscale ratio of EGFP protein and beta;actin protein bands rose with the increased voltage. RT-PCR showed that each group produced positive amplification bands, and the relative ratio of gray level of EGFP mRNA and GADPH mRNA amplified bands gradually increased with the increased voltage.Conclusion Electroporation is an effective method for gene delivery into RPE cells in vivo.
Objective To investigate the effect and mechanism of Ginkgo biloba extract EGb761 on protein expression in lightdamaged retinal pigment epithelial (RPE) cells. Methods The human RPE cells (ARPE19) were divided into normal control group, light damage group and EGb761 treatment group; the cells of latter 2 groups were exposed to the cold white light ［(2200 ± 300) lx］ to induce light damage responses. The lightdamaged RPE cells were treated with or without EGb761 (100 g/ml). The soluble protein of those cells were extracted and separated by twodimension electrophoresis and stained by silverstaining. Different proteins in the gel were analyzed by ImageMaster and identified by MALDITOFMS, and were further analyzed by mass spectrometry and bioinformatics.Results ImageMaster and MALDITOFMS identified 25, 33 and 11 different proteins between light damage group and EGb761 treatment group, between normal control and light damage group, between normal control and EGb761 treatment group of RPE cells respectively. Mass spectrometry and bioinformatics analysis successfully identified 16 proteins, including metabolic enzymes, cytoskeleton proteins, antioxidation protein and other types of proteins expressed differentially．Conclusion Protein expression profiles are different between normal control group, light damage group and Ginkgo biloba extract treatment group of RPE cells. The mechanism of protective effect of EGb761 may involve cathepsin B, heat shock protein, cytochrome C reductase, and other proteins.
Objective To observe the inhibition effect of curcumin on the proliferation of rabbit retinal pigment epithelial (RPE) cells and investigate its mechanism. Methods The 4th generation of RPE cells were selected and divided into curcumin group and blank control group. The concentration of curcumin included 10, 15, and 20 mu;g/ml. The MTT assay was used to evaluate the inhibition effect on the proliferation of RPE cells at the 24th, 48th, 72nd and 96th hour after cultured with curcumin (10, 15, and 20 mu;g/ml). The IC50 value of curcumin at different time points were calculated by Linear Regression. Flow cytometry was used to detect the effect on the cell cycle at the 72nd hour after cultured with curcumin (15 mu;g/ml); the expression and apoptosis of proliferating cell nuclear antigen (PCNA) were also determined at the 24th,48th, and 72nd hour after cultured with curcumin (15 mu;g/ml) respectively. The configuration of RPE cells were observed by transmission electron microscope. Results The IC50 value of curcumin at the 24th,48th, 72nd and 96th hour was 29.31, 17.50, 13.24, and 10.99 mu;g/ml respectively. Cell cycel analysis indicated that curcumin blocked cells in G0/G1 phase. At the 24th, 48th, and 72nd hour after cultured with curcumin (15 mu;g/ml), the expression of PCNA of RPE cells were 565.04plusmn;23.60, 473.61plusmn;36.88, and 396.15plusmn;32.45; the apoptosisrate were （12.83plusmn;0.13）%，（32.27plusmn;4.51）%，（56.81plusmn;8.67）%, respectively. The differeces of curcumin groups compared with the control group were significant (P＜0.05). Apoptosis of RPE cells was observed under transmission electron microscope. Conclusions Curcumin can inhibite the proliferation of RPE cells by inhibit the synthesization of PCNA and inducing the apoptosis of RPE cells. Curcumin may become a potential drug to prevent and treat PVR.
Objective To investigate the role of intracellular Ca2+ and MERTK in the phagocytosis of human retinal pigment epithelial (RPE) cells, and reveal the relationship between MERTK and intracellular Ca2+. Methods The cultured RPE cells were incubated with rod outer segments (ROS) at 37℃, the phagocytosis was terminated at different incubation time points. The concentration of intracellular Ca2+ was assayed by Fluro-3/AM loading methods combined with fluorescence microscope and CCD system, and the mRNA level of MERTK gene was measured by reverse transcription polymerase chain reaction (RT-PCR). Treating the RPE cells with stimulator (A23187) or inhibitor (verapamile) of intracellular Ca2+ to observe the changes of MERTK gene expression. Results ROS adhered to hRPE cells at the 15th minute, and the ingestion saturated at the 24th hour. The concentration of intracellular Ca2+ increased at the 15th minute, and kept the high level in 24 hours. The level of MERTK mRNA increased at the 5th minute, and kept the high level duration the whole incubation. When RPE cells were treated by A23187, the expression of MERTK increased in a dose-dependent manner. After RPE cells was pretreated by A23187, the expression level of MERTK was higher in the proceeding incubation groups than which in the control group except at the 3rd hour. When RPE cells were treated by verapamil, the expression level of MERTK decreased in a dosedependent manner. After RPE cells were pretreated by verapamil , the expression level of MERTK was lower in all the proceeding incubation groups than which in the control group (Plt;0.05). Conclusion MERTK gene and Ca2+ play an important role in sustaining RPE cells phagocytizing ROS. As an up-stream regulator, the receptor tyrosine kinase MERTK keeps RPE cells phagocytizing ROS by starting the intracellular Ca2+.